The design and production of unidirectional graphic articles is known and described, for example in U.S. Pat. No. 6,254,711 entitled “Method for Making Unidirectional Graphic Article” and assigned to the same assignee as the instant application.
While unidirectional graphic articles are useful in a number of display environments, these articles typically provide only one display option, for example a reflected image in a first lighting condition. That is, an image can be seen (from the viewing side of the article) in high brightness conditions such as daylight, and the image is not visible (from the viewing side of the article) in low brightness conditions such as nighttime.
Dual display films and systems are also described in the art, to provide multiple display options. That is, a film capable of showing a reflected image in a first lighting condition and a transmitted image or series of images in a second lighting condition. Examples of such films are shown, for example, in U.S. Pat. Nos. 3,888,029; 5,962,109; 6,226,906; 6,577,355; and publication numbers WO 2004042684, WO9747481, and U.S. 20040090399.